The digital age can be seen as starting a revolution in the dental field and how dental care can be provided to the patient. Digital processing and scanning technologies are generally allowing the dental practitioner to use a variety of scanning and computing technologies to supplant and/or supersede older technologies for measuring and recording an architecture of a patient's mouth; making virtual and physical models of the patient's mouth; making dental diagnoses; creating dental surgical plans; and manufacturing various dental accoutrements such as implants, prosthetics, abutments, surgical guides and other such dental devices. The current anatomical representation science and methods could be seen as being further capable of diagnosing and providing guidance in treatment planning for almost every oral-maxillofacial surgical procedure by presenting to the dental health care provider with an anatomical representation or simulation that accurately represents the true patient's anatomy. As dental digital capability becomes more economically affordable and practical, these dental services and materials, which were originally only provided only by dental labs, can now be provided by the dental practitioners' offices in less time and with lower costs.
The science behind providing true and accurate patient specific anatomical representation could be seen as comprising of an alignment, correlation, and validation of multiple sets of digital data captured by object acquisition (e.g., scanning) machines such as intra-oral optical or laser scanners, 3D optical scanners, 3D laser scanners, medical CT scanners, CBCT (i.e., Cone Beam Computed Tomography) scanners and the like. However, with so many dental digital anatomical scanning and representation capabilities or modalities (e.g., scanning devices/scanning device data processing means) that are now available to the dental field, the differences in the attributes of these various scanning and representation capabilities, individually and cumulatively, could contribute factors that may otherwise lead to inaccuracies occurring in the created anatomical representations, dental guidance and dental diagnoses unless there was a coordinating or unifying means that can be used with these capabilities.
For example, although commonly used in oral-maxillofacial treatment planning, the scan-based anatomical reconstruction method may often be ignored in lieu of simple cast fitting process. One possible reason for this preference could be that the scan-based anatomical reconstruction method could be seen as introducing possible errors into the anatomical representation capability because the scan-based anatomical reconstruction method may be subject to a dental technician's perspective on what is the thought to the best alignment of the representation of the captured portions of the jaws (e.g., bites, arches, or alike.) In this manner, the scan-based anatomical reconstruction method could substantially require a dental technician to subjectively correlate and align a higher quality detail laser or optical scan of the patient's intra-oral anatomy to lower-quality detail of the same anatomy (e.g., tooth structure) as generally provided by a CBCT (e.g., Cone Beam Computed Tomography) scan. CBCT scans are generally being seen being used for primarily capturing data regarding patient's mouth bone anatomy (e.g., cortical and trabecular.) Additionally, it could be hard to objectively identify useful dental anatomies that are not readily visible in the CBCT scans such as soft tissues, scattered data, and other objects observed in other non-CBCT scans.
Another possible limitation to the CBCT scanning is that many CBCT scanned patients (e.g., adult patients) may have existing dental metal in their mouth such as crowns, bridges, implants, etc., which can cause distortions to occur in large amounts of recorded CBCT scan data making the scanned intra-oral anatomy details unusable relative to dental planning and anatomical representation purposes. These distortions, which may be known as “scatter”, may occur when the CBCT scanner's conal x-ray beam projection into the patient's mouth hits the dental metal, which may cause the x-rays to ricochet or “scatter” in unwanted directions preventing the CBCT scanner from accurately recording the projected x-ray reflection.
Yet another limitation present in many dental scanning modalities may not accurately present an accurate representation of the true patient anatomy because these scanning modalities use only a minimal amount of data processing because only one set of scanned data is used (e.g., many times in dental planning, this is the obtained volumetric data or only that data obtained by external and artificial scan appliances and not is fully cross-referenced with other data sets as provided by another scanning device.) Patient's anatomies as reconstructed using such minimalistic scanning modalities or other such means may often discard or otherwise discount into the anatomical representation consideration a significant amount of filtered CBCT scatter data. This inability to properly process, integrate and filter the CBCT scatter data may further inhibit the proper alignment of secondary anatomy data such as dental casting model within other sets of scan data obtained from the patient.
Therefore dental practitioners using current scanning modalities may find it hard to consistently and reliably obtain a true and accurate patient-specific anatomical representation (and resulting the dental guidance and diagnose based on such anatomical representation). As a result, dental surgical and restorative treatment planning in the oral-maxillofacial environment have been continually challenged with the inaccuracies often associated with misalignment, non-representative anatomical simulation, and erroneous correlation of scan data by the attempted using of fiduciary marker-based scanning appliances to otherwise coordinate the various sets of dental digital data.
Such fiduciary marker-based scanning appliances could include a bite tray that has embedded radiopaque material (e.g., little balls of x-ray reflecting material such as titanium) having known measured qualities (e.g., size, placement, and the like) that can be inputted into the DICOM (i.e., Digital Imaging and Communications in Medicine software standards) scanning data processing system. The bite tray (with bite registration material that is not radiopaque) could inserted in the mouth of the patient, the patient then bites down on the bite registration material, and during the scan, the scanning device can “see” the radiopaque fiduciary markers of the bite tray. The fiduciary marker-based scanning appliance's known measurements can be used with the DICOM scan data processing system to help coordinate the integration, alignment, overlay and alike of scan data from multiple scanning sources by identify common reference or coordination points between various scan data sets.
The fiduciary marker-based scanning appliances may have their own scanning distorting influence that may significantly inhibit the obtained scan data from being fully orchestrating into a true patient specific virtual representation. Furthermore, fiduciary marker-based scanning appliances may present an overall inability to quantitatively calculated to what extent inaccuracies have occurred in created anatomical representations because there is substantially no one way to measure and quantify, universally and empirically, over the combined scans (due to varying detail quality), variances in scan systems themselves, and various scatter/distortion generation produced by the scans.
Further, fiduciary marker-based scanning appliances in order to be useful generally need to meet three qualifications or factors in order to maintain accuracy in such scanning modalities: 1) the fiduciary marker-based scanning appliance should be perfectly fitted in the patient's anatomy; 2) The fiduciary markers used in such an scanning appliance should be found to be perfectly consistent within both the patient scan and the scan of the fiduciary marker-based scanning appliance; and 3) the scanning appliance itself (e.g., the appliance frame) must not flex. As to the first factor, generally, a perfect fitting may be nearly impossible because many times these fiduciary marker based scanning appliances can be too rigid and awkward in size to easily conform to a patient's intra-oral environment.
The second factor may be arguably difficult to maintain as well in that various CBCT, laser, or optical scanners produce non-uniform, different quality scans. As a result, the portion of scan recording the radiographic fiduciary markers may have variances in the measurements of radiopaque fiduciary markers (e.g., the scans could show the radiopaque fiduciary markers as varying in size) as an output function of a particular scan. For example: a one type of scan could measure and report that 3 mm sized radiopaque fiduciary markers as being more or less that the actual 3 mm size of the radiopaque fiduciary markers. The reported radiopaque fiduciary marker measurement variance may occur because of the scan ambient environment, the scan system's inherent quality, and the possibility of distortion due to metallic surrounding scatter. These fiduciary marker measurement variances could result in inconsistent or improper matchup of the markers resulting in overall mis-matchup inaccuracies within the scan sets of data as processing by the scanning modality. Though such variances could be combated by increasing the number of scan markers throughout a scan, one can easily argue that more scan markers do not necessarily mean more accuracy but merely more chances for error.
For the third factor, when a scan appliance is in a patient's mouth and is bit down upon, the resilience of the radiographic fiduciary scanning appliance can temporarily flex within the patient's mouth instead of substantially conforming to the patient's dental anatomy. Once the scanning appliance is subsequently removed from the patient's mouth to be scanned, the scan appliance will revert or flex back to its original form, which will be different from the way the scan appliance was scanned in the patient's mouth leading to further possible inaccuracies.
These contributing error factors individually, cumulatively, and otherwise could introduce serious inaccuracies to the various scan(s) data sets with resulting compilation having unwanted inaccuracies.
What is needed therefore is new key or means to coordinate the various dental scan technologies and properly integrate the resulting sets of scan data in a manner that limits the possible of the occurrence of the inaccuracies as mention above. One possible solution to these inaccuracy issues could be the present invention, which may be a new method to substantially allow more accurate and true digital or virtual representation of patient specific anatomies by generally enhancing the capability of correlation between a various types of scanning modalities (e.g., CBCT scan, medical CT scan, laser scans, optical scans and the like.) The present method or process may use a bite registration means that lacks fiduciary markers, radiographic templates or shape of known dimensions (SKD) and yet generally provides a universal and consistent matchup or coordination means between various scanning modalities or capabilities. The present invention's scanning matchup or coordination method substantially provides a significantly consistent and identical matchup between the relationship and morphology of a higher detail quality scan with the relationship and morphology of the lower detail quality scans.
The invention could use a radiopaque elastomer or polymer material (e.g., a vinyl polysiloxane with 85 Shore A Durometer attributes) as a bite registration material without the use of other artificial and non-anatomical mouth structures such a bit tray, radiographic fiduciary markers and the like. When the patient bits down upon the radiopaque elastomer or polymer material placed between the jaws (e.g., placed between the alveolar ridges or dental arches) for a scan of the patient's mouth, the scanning modality during the scan can “see” and record the formed radiopaque elastomer material with the other data for that scan. That data from that subsequently created scan file can then be used and manipulated by DICOM dental software so that the formed radiopaque elastomer material can then be recognized and isolated as a structure separate from the patient's scanned anatomy. The DICOM software using the formed radiopaque elastomer material image/data can then integrate the various other scan data/images to form patient-specific virtual model of the scanned portions of the patient's anatomy.
The invention in this manner can be seen as substantially meeting three key requirements for data correlation between scanning modalities namely: 1) providing a coordination key that fits perfectly within the patient's anatomy—the bite registration material constantly and accurately meets and captures the relationship between the maxillary and mandibular occlusion (e.g., the patient's bite and its relationship to the jaw joint); 2) providing a coordinating key constantly retains the same read measurements for various scans taken of the patient in that the formed radiopaque elastomer material substantially captures dental detail (e.g., teeth) that may be consequently matched to various anatomical landmarks provided by other scans; and 3) the formed radiopaque elastomer material consistently conforms to the patient's anatomy without resistance and does not revert to pre-scan formation after removed from the patient's mouth post scan to substantially avoid the rigidity issues imposed by conventional scan trays.
In this manner, the present invention can be seen as using a formed radiopaque elastomer material to form a bit registration that can be used a coordination key to correlate patient CT scan data, dental casts or laser scans of intra-oral anatomy or optical scans of intra-oral anatomy to create true inter-arch relationship definition, accurate anatomical matching, and data merging. The present invention can be seen as generally eliminating the need to use a dental technician's artistic capabilities to substantially correct those errors/inaccuracies that may occur when combining the results of high definition scanning modalities with the results of low definition scanning modalities to generally create the anatomical representation.